The Cox Brook Dam in Northfield, VT was removed to restore ecological and hydrologic processes. Cox Brook has a mapped regulatory flood hazard area with base flood elevations published in the Flood Insurance Study and Flood Insurance Rate Map adopted by the community. National Flood Insurance Program regulations in 44 C.F.R., 65.3 require the published information to be revised when projects result in increases or decrease to base flood elevations. While the dam removal project resulted in decreases to base flood elevations, a map revision application was not submitted due to a number of considerations, including: 1) limited impact to the mapped flood hazard area; 2) very localized reductions in base flood elevations; 3) no impact to insurable buildings, and 4) disproportionately high map revision cost due to age of the flood data. As a result, certified as-built topographic information was filed with FEMA to be archived for future restudy.

Appended to the above presentation was information regarding FEMA Region 1 Hazard Mitigation Assistance (HMA) Program letter stating that the planting of tree saplings is an encroachment in a floodway in need of hydraulic analysis to ensure no increase in base flood elevations assuming the trees at full maturity. The Vermont Rivers Program strongly believes that this is a misapplication of the floodway regulations, is not consistent with HMA goals on structure acquisition parcels, and will serve as a disincentive to planting projects.

Case study summary: We had a private lands riverine restoration which included filling a drainage ditch, mechanical excavation to remove invasive cattail and culturally-accelerated sediment, and installing a low-water crossing/rock check structure. We had considerable back and forth with the USACE on this project over what was considered a complete PCN, what was acceptable for the wetland functional assessment (quantitative versus qualitative), and what was acceptable for the wetland delineation (and the geography that the delineation needed to cover.) The NWP #27 authorization took about 14 months to obtain, with approximately 6 months of this delay being due to having to re-complete the delineation and having to wait until the growing season to do so. Additionally, within this time, there were three times that the USACE was outside of the 30 or 45 day calendar day response window.